Filter- and cooling elements for gas generators in airbag systems are known from DE 10 2004 032 609 A1, which are constructed in several layers with a plurality of metallic individual elements and have a plurality of passage openings, provided in or between the individual elements, for a fluid medium. These filters are intended to serve as an alternative to conventional metallic filters in gas generators, which consist of a knitted mesh pressed into shape. For the knitted mesh filters, a metal wire is processed into knitted fabrics or socks by knitting machines and is then pressed into the respectively desired shape, for example a hollow cylinder. However, the knitted mesh filters which are produced in this way have a non-homogeneous distribution of the pore volume. Moreover, in the conventional knitted mesh filters the formation of defects can frequently be observed, where a characteristic pore volume, predetermined by the loop radius a and the mesh width, is distinctly exceeded and cavities, tears or splits occur which are visible to the naked eye.
Thus, it is an object of the present invention to provide favourably priced alternatives to filters made of pressed knitted metal wire, which are adapted for use in a gas generator for cooling the gas stream and for separating residues of propellant and larger particles of propellant.